The present invention generally relates to wireless communication systems and particularly relates to the use of router-based radio base stations in a base station network.
Wireless communication systems, such as cellular communication systems, typically comprise some type of radio access network that allows users of mobile terminals operating within the network's service area to communicate with other mobile terminal users, and users of other communication networks, such as the Public Switched Telephone Network (PSTN). In cellular communication systems, the radio access network typically comprises at least one base station controller and a number of radio base stations. Typically each radio base station provides coverage over a defined area, referred to as a “cell,” and connects to the base station controller through a landline link, such as T1/E1, or by some line-of-sight wireless link, such as microwave.
The radio base stations are usually arranged such that the cells provide the best possible coverage over the entirety of the service area. Even so, there are oftentimes smaller, isolated areas within one or more cells where service is unavailable or of reduced quality. This may be particular true in urban areas with rows of tall buildings that block signals and create coverage gaps. Other areas, such as in and around malls or other large, enclosed structures, also may have poor coverage.
One approach to providing coverage in such areas involves the use of “pico” radio base stations (RBSs). Pico denotes the relatively small coverage area of the typical pico RBS. Usually, a number of pico RBSs are distributed within an area where coverage would otherwise be a problem. For example, one or more pico RBSs may be distributed within a shopping mall to provide communication coverage.
Although the use of pico RBSs permits more flexibility in terms of radio coverage, certain limitations affect their use. For example, the typical pico RBS requires a dedicated communications link back to the base station controller, which link is commonly implemented as a T1/E1 line. Providing such connections may be problematic, particularly in crowded urban installations. Moreover, costs associated with providing and maintaining landline links (e.g., T1/E1) to a potentially large number of associated pico RBSs are often prohibitive.